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Month: April 2015

While hurlers across MLB have been throwing fewer sinkers in recent years, the Pirates have increased their usage of the pitch. Per MLBAM’s classifications, 37% of Pittsburgh’s pitches were sinkers (including two-seam fastballs) in 2014, eight percentage points ahead of any other team. The Bucs have ticked down to 35% so far in 2015 (and been surpassed by Oakland), but they are still among the league’s leaders in sinkers.

As a follow-up to yesterday’s chart, here is a graph of aggregate pitch types in MLB since 2010. Pitch selection has been remarkably consistent over time; in 2015, all offspeed pitches are within 0.5% of their usage five years earlier. The exception is the sinker (which includes two-seam fastballs), which has fallen from 25% to 22% since 2010, mostly replaced by four-seam fastballs.

A significant caveat: Most pitch types exist on a spectrum, so MLBAM’s pitch classification algorithm is not perfect — especially for distinguishing between different fastball types. So the apparent decrease in sinkers could reflect changing classifications instead of a change in pitchers’ actual behavior. Additionally, my hypothesis is that the 2013 drop in sliders is due to a classification change (especially given the associated rise in curveballs), since it is out of line with all other years.

On aggregate, pitchers are throwing mostly the same types of pitches in 2015 as they did last season. The share of curveballs (per MLBAM classifications) has declined by a full percentage point, replaced by a slightly greater share of changeups, fastballs and sliders. Four-seam fastballs remain the most common pitch at about 35%, followed by sinkers (including two-seam fastballs) at 22%.

The Red Sox are leading the AL East with a 9-5 record through Tuesday’s games, thanks in large part to a prolific offense that has scored more than five runs per game. They’ve been a bit lucky to do so, however. 14 Red Sox have reached base on error so far, four more than any other team in baseball and more than twice the MLB average. Boston will hit well regardless — and reaching base on error is a skill to some degree — but it can’t count on so many opposing miscues going forward.

The most common balls in play come off the bat at 85-100 mph, but exit speeds in 2015 have ranged from 30-119 mph, according to MLBAM data compiled by Baseball Savant. (Data excludes bunts and approximately 40% of batted balls for which speed was unavailable.) Not surprisingly, harder-hit balls are more successful; 59% of balls at 100+ mph became hits, compared to just 21% of balls at 75 mph and slower. There are also a few errors in the raw data, such as this Mike Trout homer, which was recorded at a mere 48 mph.

So far, it appears MLB’s new pace of play guidelines have slightly sped up games. As shown above, when controlling for plate appearances, games been about five minutes slower this season than they were in 2014. (Only nine-inning games were included; 2015 data represents games through April 15, measured against the corresponding period in 2014.)

This chart shows the distribution of MLB Opening Days in the expansion era. Twenty-eight teams opened the 2015 season on Monday, the most squads ever to begin their season at once. The Cardinals and Cubs started a day earlier on April 5, tied for the latest league opener since the 1995 strike.